Ventilation for dynamo-electric machines



Dec. 26, 1922.

H. S. BALDWIN. VENTILATION FOR DYNAMO ELECTRIC MACHINES.

FILED MAR-5,1921- Inventor': Henry 5Baldwm,

b 4 4. M H Hisflltorney.

up a circulation of air within the machine.

Patented Dec. 26, 1922.

UNITED STATES PATENT OFFICE.

HENRY S. BALDWIN, OF LYNN, MASSACHUSETTS, ASSIGNOR TO GENERAL ELECTRIC COMPANY, A CORPOBATION OF NEW YORK.

VENTILATION FOR DYNAMO-ELECTRIC MACHINES.

Application filed March 5, 1921.

within the machine itself. While this is eflicient, in some cases it becomes of importance to save as much space as possible on the inside of the machine and thus to reduce its size and weight.

The main object of my invention is to provide ventilation in such a way that no extra space is needed inside the enclosed machine, and another object is to enable such a ventilating scheme to be used in any existing enclosed machine. I attain these objects by providing means exterior of the machine for creating a blast of air and directing this blast over openings in the machine frame which otherwise totally encloses the machine. This blast of air operates on the principle of an ejector and creates a partial vacuum in the enclosed machine. This partial vacuum serves to set Air is sucked into the casing of the machine either through the same apertures over which the blast flows, or through other holes located in the casing. For a better understanding of my invention, reference is to be had to the following specification, -together with the accompanying drawings; in

which Fig. lis a longitudinal sectional view.

of a dynamo electric machine utilizing my invention; and Fig. 2 is an end view partly in section showing how the ventilation may be easily controlled.

Referring now more in detail to the drawings, in which like reference characters refer to like parts throughout, the dynamo electric machine 11 has a'rotating armature 12 mounted in any appropriate manner on a rotatable shaft 13. This shaft 13 in the present instance is shown as supported in roller bearings at several points along the axis. Various mechanisms may be included within the frame; in the present instance gear drives areshown. The field apertures and retain them in that position.

Serial No. 449,672.

system comprises a plurality of field coils 14, all of them appropriately supported in the magnet frame 15. totally enclosed as by means of the end shields 16. These end shields .16 have radial openings or apertures 17, each extending approximately for 135 around a circle, and forming long, narrow slits. Ap-.

propriate means are provided, such as a fan 18, for producing a blast of air across these apertures 17. This fan is mounted so asto be directly driven by the shaft of the machine. In order to direct the blast of air opposite these apertures 17, I may provide appropriately hinged ventilation covers 19,

most clearly shown in Fig. 2', each carrying integral bafiie plates 20 so located angularly The machine is j with respect to the blast of air that it de- 1 fleets it down close to the apertures 17. It is evident that by this means a draft of air produced by the fan is forced past the apertures 17 and creates in a well known manner a partial vacuum within the casing.

The ventilation covers 19, as stated heretofore, are hinged, as for example, at 21, and are so arranged that limited angular movement about these hinges is permitted.

This arrangement is shown most clearly in- Fig. 2 wherein the upper ventilation cover 20 is opened up so as to leave the aperture 17 uncovered, while the lower-ventilation cover 19 is closed so that the lower aperture 17 is covered. A spring'22 appropriately supported on the stationary portion of the end shield or frame is so arranged that it tends to open the ventilation cover 19. To

close the ventilation covers, the pivoted handles 23 are utilized, which handles are located. at opposite ends from the pivots 21.' These pivoted levers by means of the links 24 pull the ventilation covers 19 toward the in the manner clearly shown in Fig. 2. When the handles 23 are rotated about 180 so as to open the ventilation covers, the springs 22 are free to actand serve to rotate the ventilation covers 19 slightly above the pivots 21, until they are restrained from clearly illustrated in the upper half of Fig. 2.

The directions taken by the currents of air in ventilating the machine may be as shown by the arrows in Fig. 1. Although in this instance I have shown arrows leadfurther movement by the links'24. This is sa v p of. the casing rma other aperturesg ""ing into the casin'g through the "apertures 17 it'is evident that theair to the interior be supplied through urthermore, it ;-.is also "evident that the dynamo electric: machine g nay be'operated either as a generator or as obtained by this ,meansi While' I 'have -shoWn and described a pr ferr'ed" mbodiment *"of my invention, I do? not wish-toiibelimited thereto but aim to embrace in-theap I. 1

new and desire to secure I which an aperture is provided in one-end of the enclosing frame, and in which the ventilatin fluid is] caused to move by "an exterior ianmounted on the shaft of said machine adjacent said end, characterized by chine. v a dynamo electric'jmachine having a 'dti end shields provided with apertures l sing'u one end'of saidmachine, covers f-for said apertures-1 means whereby said nded claims all modifi cations "falling -fairlylvwith in ;the scope, of ,;ny;inve i1tionh I hat-I claim as Letters .Patent ofthe UnitedyStateq 11A ventilating system'for a dynamo electric machine of the enclosedhtype in being so shaped that when itis in a partiall opened p0sition,-it causes ventilating to flow through the interior of said machineand around the. exterior of said maovers may be opened slightlygla fanvmountdon the shaft of said, .1na'chine outside of he end shields for producing a blast of air, and baflie -blades formed integral with said vers'so arranged asto guide the air over theapertures., ,.v

' -1 '-'*3. In'adynamo electric machine having agshaft, end shields closing up one end of said machine, long narrow apertures in the end "shields, hinged covers for said tapertures, means.,whereby said covers may be lifted slightlyhaway from said apertures, a fan mounted on the shafitof said machine ,outside of the end shields for producing a blast of air, and baflie plates formed integral 'With the hinged jcovers so arranged p as to guide the air over the apertures.

the fact that said aperture is provided with r a cover adapted to beheld m a partially open or entirely closed position, said cover In witness whereof, I have hereunto set my hand'this 2nd. day offMarch [1921. HENRY is. BALDWIN. 

